Add new columns to existing table in a migration in Laravel

问题

I want to add some new columns in my existing table users in laravel.

I have already googling for that and following those search I have already created migration using the command php artisan make:migration add_columns_to_users.

add_columns_to_users.php

public function up()
{
    Schema::table('users', function($table) {
        $table->string('address');
        $table->string('city');
        $table->string('tribe');
        $table->string('country');
        $table->integer('student_id');
        $table->string('tribe_university_name');
        $table->string('student_program_of_study');
        $table->string('faculty');
        $table->string('level');
    });
}

public function down()
{
    Schema::table('users', function($table) {
        $table->dropColumn('address');
        $table->dropColumn('city');
        $table->dropColumn('tribe');
        $table->dropColumn('country');
        $table->dropColumn('student_id');
        $table->dropColumn('tribe_university_name');
        $table->dropColumn('faculty');
        $table->dropColumn('level');
    });
}

After creation, I run this command php artisan migrate.

But got the same error:

Base table or view already exists: 1050 Table 'users' already exists (SQL: create table users (id int unsigned not null auto_increment primary key, name varchar(255) not null, email varchar(255) not null, password varchar(255) not null, remember_token varchar(100) null, created_at timestamp null, updated_at timestamp null) default character set utf8 collate utf8_unicode_ci)

Full name of user table 2014_10_12_000000_create_users_table.php and the other name is 2019_04_11_074552_add_column_to_users.php

How to solve this?

My main query is How to add new columns in my existing table?

回答1:

If you check at the error trace:

Base table or view already exists: 1050 Table 'users' already exists

This means that the users table already exists so when you run your migrations it is trying to create a table that is already created in your database.

Note: Don't forget to backup your database first

Delete users table from the database also delete users entries from migrations table.

After, execute the migrate Artisan command:php artisan migrate

---

Now another your Question is: How to add new columns in my existing table?

You have to create a table using this command:

php artisan make:migration create_users_table

The output you got it like this: Created Migration: 2019_04_12_070152_create_users_table

Your Migration structure is something this:

public function up()
    {
        Schema::create('users', function (Blueprint $table) {
            $table->increments('id');
            $table->string('name');
            $table->string('email')->unique();
            $table->string('password');
            $table->rememberToken();
            $table->timestamps();
        });
    }

Now you want to add new columns in your existing users table

php artisan make:migration add_phone_number_to_users_table --table=users

use the Schema::table() method (as you're accessing an existing table, not creating a new one). And you can add a column like this:

public function up()
{
     Schema::table('users', function (Blueprint $table) {
         $table->string('phonenumber')->after('name'); // use this for field after specific column.
     });
}

/**
 * Reverse the migrations.
 *
 * @return void
 */
public function down()
{
    Schema::table('users', function (Blueprint $table) {
        $table->dropColumn('phonenumber');
    });
}

After, you can run your migrations: php artisan migrate

Your new columns(phonenumber) are now added to your existing users table, which you can view in your database.

If you have still any doubt, see this video

回答2:

The problem comes from the php artisan migrate that will try to migrate both files when 2014_10_12_000000_create_users_table.php is already migrated, so IMO two possible solutions here :

1. Rollback the users table from the DB and rerun the migrate cmd.
2. Add the migration name inside the migrations table so the cmd will not try to run it for the second time.

回答3:

Modifying current migration wont work, because it's entry in migration table is already there. So to make any changes in already existing table, you need to create new migration script.

// remember `create` replaced by `table` here  

Schema::table('users', function (Blueprint $table) { 
    // add whichever new columns you want to
});

Follow these steps,

1. php artisan make:migrate modify_user_table
2. open modify_user_table file in database/migrations directory

3. Add new columns as at top I wrote.

4. Now save the file after adding new columns into new migration file

5. cmd -> php artisan migrate

EDIT

1. If there is no user data then Open 2014_10_12_000000_create_users_table.php file and add Schema::dropIfExists('users'); before Schema::create('users'... line.

2. If there is data then you can take a backup, again follow the above step 1.

回答4:

Please do the step 1. php artisan migrate:reset Step 2: Go to your database using PHPmyadmin (or similar) and delete all remaining tables - including the migration table.

After all please do Step 3 php artisan migrate

回答5:

You need do little modification in your artisan command

artisan make:migration add_columns_to_users_table

You then need to use the Schema::table() method (as you're accessing an existing table, not creating a new one). And you can add a column like this

  public function up()
  {
     Schema::table('users', function($table) {
          $table->type('column');
      });
   }

add the rollback option:

 public function down()
{
    Schema::table('users', function($table) {
        $table->dropColumn('column');
    });
 }

Then you can run your migrations:

 php artisan migrate

来源：https://stackoverflow.com/questions/55629242/add-new-columns-to-existing-table-in-a-migration-in-laravel